Think about the kind of services that Microsoft would be acquiring.. along with a huge customer base. Very good potential to upsell or promote Microsoft products and services.
As Long Zheng listed out.. there is a huge overlap of web services between Yahoo! and Microsoft. Would be interesting to see how Microsoft goes about consolidating these services if this acquisition becomes a relality.
Coming back to Microsoft's press release.. if you had read Steve Ballmer's letter to Yahoo Board of Directors, you can feel a threatening tone in it.. This is what the letter says:
Depending on the nature of your response, Microsoft reserves the right to pursue all necessary steps to ensure that Yahoo!’s shareholders are provided with the opportunity to realize the value inherent in our proposal.And this how it translates to.. :)
Guys.. dont give a bullshit answer. If you don't want to be acquired, then we'll take it up with the shareholders.
You can get more insight about this news in this post in The New York Times.
My personal feeling is that.. Yahoo! is not doing very good. In fact, its dying slowly. It is better that it gets acquired by Microsoft.. better for the company and its shareholders.